


Flame versus Fullmetal

by vino_and_doggos



Category: Avatar: The Last Airbender, Fullmetal Alchemist - All Media Types
Genre: AtLA AU, FMA Secret Santa 2018, Firebender!Roy, Gen, evil!Roy
Language: English
Status: Completed
Published: 2018-12-26
Updated: 2018-12-26
Packaged: 2019-09-28 00:08:26
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 2,636
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/17172095
Author URL: https://archiveofourown.org/users/vino_and_doggos/pseuds/vino_and_doggos
Summary: The Fire Nation's Army is being attacked by an earthbender. Fire Lord Ozai sends in one of his men - Colonel Roy Mustang - to apprehend the troublemaker.Written for FMA Secret Santa 2018!





	Flame versus Fullmetal

**Author's Note:**

  * For [chocoches](https://archiveofourown.org/users/chocoches/gifts).



> Written for [chocolateches](https://chocolateches.tumblr.com/) for FMA Secret Santa 2018!! I kind of creeped on your tumblr a bit and found that you liked both FMA and ATLA, as well as had a penchant for Evil!Roy... So I couldn't pass up an evil, firebending Roy. Happy holidays, and I sincerely hope you like it!!
> 
> As always, eternal thanks and praise goes [A Passing Housewife](https://archiveofourown.org/users/NPC_MPDG/pseuds/A%20Passing%20Housewife/works?fandom_id=824702) for being the best beta (and wonderful friend) in the world.

Colonel Roy Mustang looked at his small battalion of Fire Nation soldiers before him. Inwardly scoffing once again at the ragtag group of firebenders and foot soldiers, Roy ensured that they all understood their orders for the day: rounding up another batch of earthbenders to be sent to Boiling Rock.

Maybe this time they would catch the troublesome one.

At first, it was small things. Boulders placed inconveniently throughout the Fire Nation encampment. Minor earthquakes in the dead of night. Large divots in roads. Big enough to wreak havoc on a supply-laden carriage, but not destructive enough that the komodo rhinos couldn’t navigate on their own.

Then, bigger things began to happen.

Boulders were thrown at soldiers arresting an earthbender. The earthbender in custody was not the one throwing rocks; Roy was sure of it. But as they spread out and searched the area, no one else was found.

Their campsite was utterly destroyed following an earthquake that caused the ground to collapse beneath their feet. Three soldiers, one bender and two non-benders, perished in the accident. The colonel was convinced that it was no accident.

Worst yet, one of Roy’s particularly cruel (but effective) soldiers was found at the back of an alley.

A four-foot stone spike pierced the chest of his limp, lifeless body. Thick, scarlet blood coated the unnaturally jagged protrusion of earth and pooled at the soldier’s feet. His eyes were still wide with awe and fear.

The vigilante needed to be stopped. And that’s why Fire Lord Ozai dispatched Colonel Roy Mustang to the area.

Roy felt that the best way to quash the hopes of the city of Dōngchéng of was to catch the agitator. In a place larger than the small villages the Earth Kingdom was known for, yet smaller than Ba Sing Se and Omashu, it shouldn’t be as difficult as it was proving to be.

Dismissing the soldiers, Roy sat down behind his war room’s table (which was technically a war tent). The colonel’s crimson and black uniform swished and settled comfortably around him, the pauldrons at his shoulders making a gentle noise as he leaned against the tall-backed chair. Roy ran a hand through his already-mussed hair, the jet black locks falling somehow artfully over his forehead once more. Despite being only 29, he was one of the most promising soldiers, a firebender that was in line to become the immediate general to the Fire Lord.

Mustang looked down at the map of all four nations and plans for the Fire Nation’s expansion to unite the world under the flag of the flame - a new nation called Amestris. Sighing, the colonel cradled his forehead in his palm. Could this, apprehending a small-time earthbender, be the key to becoming a general for Fire Lord Ozai?

Men shouting from outside Mustang’s war room pulled the colonel from his thoughts. What nonsense had that idiotic group of soldiers gotten themselves into now? Reluctantly rising and making his way towards the slit in the tent, he felt the tell-tale rumbling of earthbending. Roy’s eyes narrowed as he flung himself out into the fray.

A young blonde girl with long, braided hair was facing three of his firebending soldiers. He rushed toward them, his pace hurried but not frantic as it wouldn’t do good to look flustered in front of his command. He reached the halfway point when a kick from the earthbender flung three pieces from the ground directly at each soldier, wiping them all out in one fell swoop.

Forcing himself to remain calm, Mustang shouted across the hubbub, “So we finally get to meet face to face. And what would your name be?”

“Heh! Like I’d ever tell you my name,” a decidedly male voice answered him. The boy looked to be around the age of ten, a dark green tunic falling over brown pants. The sleeveless tunic allowed for him to move freely to bend, but Mustang noticed that the blond’s right arm appeared atrophied in comparison to his left.

The colonel ensured that the surprise didn’t register on his face before continuing.

“Well, I can’t keep calling you The Earthbending Assailant, now can I?”

“That name isn’t nearly cool enough,” the young man complained. “How about Fullmetal?” the blond said, a cocky smirk gracing his face.

“Fullmetal,” Roy smirked right back, “I think I like that. Well, in that case, you can call me Flame!” articulating the last word with an impressive display of firebending, meant to intimidate more than maim.

Laughter echoed through the valley as Fullmetal appraised the colonel in front of him. “Showy!” he said sarcastically. “Maybe next time you’ll pay more attention to your opponent,” the blond said as he jerked his chin upward.

Roy looked above his head just in time to see a chunk of earth losing altitude _fast_. The colonel dove to his left, landing and rolling in the dust as a crash sounded over his right shoulder. Infuriated and somewhat humiliated, Roy rose to his feet and swiped the dust from his red and black uniform.

Colonel Roy Mustang, the Flame, snapped.

Columns of fire surrounded the earthbender, effectively trapping him behind walls of flame. Fullmetal retaliated by attempting to bring sheets of rock up around himself as a shield, but at the last second, Mustang closed the towering inferno, ensuring that the boy was unable to move at all. Breathing deeply, the colonel smirked and knew he was just getting started.

Colonel Mustang moved towards Fullmetal at a deadly slow speed, deliberately ensuring each step was heavily hitting the packed ground, menacing in sound as well as look. As Roy came closer, he realized Fullmetal was sweating - whether from the heat or his nerves was anyone’s guess, but the glint of determination was still in the blond’s eyes.

Mustang was ready to quash that gleam of hope. He chuckled menacingly as Fullmetal met his eyes.

“Did you know,” the colonel started, “that firebending is not just producing fire?” He smirked and watched as the earthbender visibly swallowed.

“Accomplished firebenders are able to control fire in ways that run-of-the-mill firebenders are not. For example, I can make this fire burn bigger, hotter than it should,” he explained with a complicated kata that raised the temperature of the fire noticeably. Fullmetal whimpered; the colonel considered himself lucky that he was able to hear it at all over the crackling inferno.

“But something that I have figured out,” Mustang continued, “is how to manipulate the fire so that the oxygen is so depleted that you’ll suffocate.”

Watching eyes widen in fear was one of Colonel Roy Mustang’s favorite parts of his job. He wasn’t disappointed when the striking golden eyes of his captive did exactly that.

The firebender began a kata that moved his hands and arms in a complicated pattern and watched with delight as Fullmetal struggled to breathe. He could tell that the kid was on the verge of collapsing and pushed it just a bit farther.

Fullmetal went limp.

Mustang relinquished the fires burning around the earthbender, allowing oxygen back into the space. Fullmetal was unconscious just as he’d hoped.

A small crowd of Fire Nation soldiers stood watch as Roy calmly straightened his uniform. He motioned two soldiers forward. “Take him to the interrogation area. Tie him up. Make sure all of the metal shields are in place so he can’t bend. Set a guard. Get me when he wakes up.” Though the orders were barked appropriately for a colonel of high regard, his voice was ragged, simultaneously filled with accomplishment and tinged with exhaustion.

The men scrambled to follow their colonel’s orders, dragging the blond away.

Roy needed a drink.

 

* * *

 

Unfortunately, the opportunity to pour himself a stiff drink never presented itself. Cleaning up the camp took far too long for his liking. Even after that tedious task was done, Roy still had to write General Bujing about the new captive, reschedule the earthbender sweep in the village, and debrief the platoon regarding the day’s events. So much to do, so little time.

As he finished his letter, his adjutant entered the room. Her blonde hair, unusual for a native of the Fire nation, was clipped in its normal, professional fashion at the back of her head, never touching her black uniform as demanded of female soldiers by the Fire Lord himself.

“Sir,” she started, her voice firm. “The boy is awake.”

“Hm,” Mustang sounded in response. He stood muttering, “Thank you, Hawkeye,” as he exited.

Entering the metal-shielded room, the colonel’s face split into an evil grin seeing the earthbender bound and surrounded by guards. Shadows crossing the man’s visage made the grin appear even more sinister, as the light from the torches placed around the room flickered. With every shift of the flame, more darkness encroached on Mustang’s face as he saw the small person, weakened and unable to escape. He nodded, dismissing the soldiers to take their posts at the door instead.

Fullmetal sat on the iron stool that was attached to the floor, jaw set and eyes glaring. His head was raised, fully upturned and making eye contact with the colonel. Despite the flame also illuminating his face, somehow the flickering did not travel into the valleys made by domination; rather, the flame just reflected youth, promise, and determination. Mustang smirked in response.

“What were your goals when you started this?” the colonel asked condescendingly. “Did you really think you would be able to take down the entire Fire Nation by wiping out a small platoon of soldiers?”

Silence.

“What’s the matter, Fullmetal?” he taunted. “Cat owl got your tongue?”

Another glare was the only response. Mustang decided to play dirty.

“I wonder if you have any family that will even miss you. Whether you’re sent to Boiling Rock or you’re dead by my hand, they’ll never know.”

A shadow passed over the younger male’s face; the colonel knew he found a nick in the boy’s armor. Now to exploit it.

“It really is a shame,” the dark-haired man continued. “Maybe your mother would cry. She would be missing her son, after all.”

A soft snarl escaped Fullmetal.

“Do you have siblings?” Mustang waited for a response that would never come, then continued as if the silence answered him.

“You’ve made your brother or sister mourn you. If you hadn’t acted out, you would have been able to go home tonight. Will they cry, as well, when they realize you aren’t coming home?”

“SHUT UP!” Fullmetal screamed. Mustang smiled evilly. Fire Lord Ozai was right, he realized; all other benders are unworthy of survival past the unification of all lands under the Fire Nation. A firebender wouldn’t have given up, wouldn’t have caved so easily. All other benders were weak in comparison to firebenders. Before, this was a platitude that Roy believed because he was told to believe it. Now, he was seeing it with his own eyes.

"Judging by your actions, you’re the oldest child,” the colonel deduced. “I grew up with many siblings myself, and although I fell right in the middle, I remember how my older sisters acted. So which is it, Fullmetal? Do you have a younger sister at home? Or a younger brother? Maybe both?” Roy prodded. When he was met with hard eyes, he tried again.

“I’ll bet it’s a younger sister. Many older brothers aren’t fond of their younger brothers, or so I’m told. Younger sisters, though… you’ll need to protect them from the harsh realities of life, won’t you? Boys that will break their heart, bullies that will push them into the dirt, bad things -”

“It’s a brother!” the blond exclaimed. “My younger brother,” he clarified quietly. Even softer, almost under his breath, Fullmetal continued, “And he’s sick.” Almost as soon as it was out of his mouth, the boy looked horrified that he had revealed so much information.

Colonel Mustang puffed out his lower lip in a pout. If the kid thought playing the sob story would work, he was sadly mistaken. “What a shame that you won’t ever see him again, then.”

“No, no, no,” Fullmetal said quietly. As he repeated the word, it grew louder and louder. “No, no, _no_ , you can’t! He’s sick; he needs me! You _can’t_!”

“I can, and I will. I’ll ask you again, Fullmetal: what did you think would happen when you continually attacked Fire Nation soldiers and our camp? Did you think you would get away with it?”

The kid’s head dropped, his hair hanging over his eyes. “I don’t know,” he admitted quietly. “I thought that maybe the avatar would -”

“Would what?” interrupted Mustang. “See an earthbender attacking firebenders and step in? And on whose side would you have liked him to intervene? _You_ were the one attacking!”

“Like hell!” Fullmetal spat. “Have you been paying attention? The Fire Nation is trying to capture Ba Sing Se! You’re getting rid of all of the benders by sending them to prison, and Ozai is just plotting to become some sort of supreme leader. Would I have been any better letting that happen, Mustang? Tell me!” Throughout the tirade, the blond’s voice continually rose in pitch and volume, becoming more frantic.

“You would have been better to obey me,” Mustang said, deadly quiet. He approached Fullmetal, towering over him, and bent down to stare straight into the boy’s burning eyes. “I am the law.”

Fullmetal was a spitfire, Roy could tell. He didn’t expect the physical spit, though, and only after it hit his face did he realize that there was only one way to deal with this brat.

Raising his hand, he hit Fullmetal - _hard_ \- and if he weren’t bound to the chair that was bolted to the floor, the boy would have flown across the room. The blond’s head snapped back to meet the eyes of the colonel before him, a red mark already appearing on the boy’s cheek.

“You’ll pay for that, you fucking BRAT!” Mustang yelled, smacking the boy again. The sound echoed off the metal walls.

In the blink of an eye, Colonel Roy Mustang produced fire from his hands, ready to direct it at the face of the child in front of him. At the last second, though, he felt heavy hands grasp his shoulder, jerking him backward.

“Colonel Mustang, what are you doing?” a rough voice with a heavy lilt asked.

“I thought I was very clear in my intentions, Captain Havoc,” he responded sternly, letting the flames he carried diminish but not extinguish entirely.

“Colonel, you’re better than this. He’s just a damn kid,” Havoc said, a pleading tone evident but not explicit.

“A kid that won’t obey my orders,” Mustang reminded his captain, danger seeping into his voice.

Havoc shook his head. “That doesn’t mean you should kill him, sir.” He paused for a moment before taking a different approach.

“If you kill him, they’ll launch an investigation. You could face an Agni Kai. It doesn’t matter that he’s a bender or the one they’ve been searching for. Turning him in alive is far better than turning him in dead.”

Another lull.

“Fine,” Mustang answered grudgingly, his eyes still alive with the light only a firebender could muster. “Take him to Boiling Rock. He’s their problem now,” he said coldly, stalking out of the room.

Mustang went back to his tent, still thinking about the kid. About Fullmetal. He knew he let his temper get the best of him; if there was one thing Roy couldn’t stand, it was a lack of respect. This child, this boy, knew exactly how to push every one of his buttons. The two could become quite formidable adversaries given a few years.

A smirk began to form on the officer’s face.

Flame versus Fullmetal.

Roy liked the sound of that.


End file.
